Boston Massacre, one of the incidents that led to the American Revolution. The people of Boston, Massachusetts, resented the garrisoning of British troops in the city. On the night of March 5, 1770, there were rumors of British brutality, and tension heightened between townspeople and soldiers. A crowd gathered at the Custom House. A group led by Crispus Attucks began taunting the sentry and hurling snowballs. Captain Thomas Preston and eight redcoats rushed to his aid. In the confusion, the soldiers fired. Bullets killed Attucks and two other civilians and wounded eight, two of them fatally.

The soldiers were tried for murder. Defended by John Adams and Josiah Quincy, Jr., Preston and six soldiers were acquitted. Two were found guilty of manslaughter and were branded on the thumb. Samuel Adams used the incident as propaganda to inflame anti-British feeling in Massachusetts.